Development and Validation of the iDI: A Short Self-Rating Disability Instrument for Low Back Pain Disorders.

STUDY DESIGN: Cross-sectional and longitudinal validation study. OBJECTIVE: Development and validation of a short, reliable, and valid questionnaire for the assessment of low back pain-related disability. METHODS: The iDI was created in a stepwise procedure: (1) its development was based on the literature and theoretical consideration; (2) outcome data were collected and evaluated in a pilot study; (3) final validations were performed based on an international multicenter spine surgery outcome study including 514 patients; (4) the iDI was programmed for a tablet computer (iPad) and tested for its clinical practicability. RESULTS: The final version of the iDI comprises of 8 simple questions related to different aspects of disability with a 5-point Likert-type answer scale. The iDI compared very well to the Oswestry Disability Index in terms of reliability and validity. The iDI was demonstrated to be suitable for data assessment on a tablet computer (iPad). CONCLUSIONS: The iDI is a short, valid, and practicable tool that facilitates routine quality assessment in terms of low back pain-related disability.

Total disc replacement for chronic discogenic low back pain: a Cochrane review.

STUDY DESIGN: Systematic literature review. OBJECTIVE: To assess the effect of total disc replacement for chronic low back pain due to lumbar degenerative disc disease compared with fusion or other treatment options. SUMMARY OF BACKGROUND DATA: There is an increasing use in disc replacement devices for degenerative disc disease, but their effectiveness compared with other interventions such as fusion of the motion segment or conservative treatment remains unclear. METHODS: A comprehensive search in PubMedCentral, MEDLINE, EMBASE, BIOSIS, ClinicalTrials.gov, and FDA trials register was conducted. Randomized controlled trials comparing total disc replacement with any other intervention for degenerative disc disease were included. Risk of bias was assessed using the criteria of the Cochrane Back Review Group. Quality of evidence was graded according to the GRADE approach. Two review authors independently selected studies, assessed risk of bias, and extracted data. Results and upper bounds of confidence intervals were compared with predefined clinically relevant differences. RESULTS: We included 7 randomized controlled trials with a follow-up of 24 months. There is risk of bias in the included studies due to sponsoring and absence of any kind of blinding. One study compared disc replacement with rehabilitation and found a significant advantage in favor of surgery, which, however, did not reach the predefined threshold. Six studies compared disc replacement with fusion and found that the mean improvement in visual analogue scale score of back pain was 5.2 mm higher (2 studies; 95% confidence interval 0.2-10.3) with a low quality of evidence. The improvement of Oswestry disability index score at 24 months in the disc replacement group was 4.3 points more than in the fusion group (5 studies; 95% confidence interval 1.85-6.68) with a low quality of evidence. Both upper bounds of the confidence intervals were below the predefined clinically relevant difference. CONCLUSION: Although statistically significant, the differences in clinical improvement were not beyond generally accepted boundaries for clinical relevance. Prevention of adjacent level disease and/or facet joint degeneration was not properly assessed. Therefore, because we think that harm and complications may occur after some years, the spine surgery community should be prudent to adopt this technology on a large scale, despite the fact that total disc replacement seems to be effective in treating low back pain in selected patients, and in the short term is at least equivalent to fusion surgery.

Implant survival analysis and failure modes of the X-Stop interspinous distraction device.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To review the clinical outcome, implant survivorship and reasons for failure after X-Stop implantation. SUMMARY OF BACKGROUND DATA: Conflicting data exist concerning clinical outcome of the X-Stop interspinous spacer and little information is being published about implant survivorship and the need for revision surgery. METHODS: This retrospective review evaluated 46 patients who underwent implantation of the X-Stop interspinous spacer for the treatment of neurogenic claudication. After a mean follow-up of 40 months, pain levels, 36-Item Short Form Health Survey (SF-36), Oswestry Disability Index (ODI), and the need for subsequent surgery were assessed and a Kaplan-Meier survivorship analysis was performed. RESULTS: Within the follow-up period, the revision rate was found to be 30.4%. Lack of improvement at 6-week follow-up correlated well with subsequent revision surgery, which predominantly took place within 12 months after the index surgery. In patients who did not need to undergo revision surgery, clinical outcome parameters improved significantly. Kaplan-Meier survivorship analysis predicted an implant survival probability of 0.68 at 48 months postoperatively. CONCLUSION: Clinical outcome after X-Stop implantation might be considerably less favorable than when it was being published previously. Patient selection might be a reason for early revision surgery. More criteria for better X-Stop indications might be needed.

Total disc replacement for chronic back pain in the presence of disc degeneration.

BACKGROUND: In the search for better surgical treatment of chronic low-back pain (LBP) in the presence of disc degeneration, total disc replacement has received increasing attention in recent years. A possible advantage of total disc replacement compared with fusion is maintained mobility at the operated level, which has been suggested to reduce the chance of adjacent segment degeneration. OBJECTIVES: The aim of this systematic review was to assess the effect of total disc replacement for chronic low-back pain in the presence of lumbar disc degeneration compared with other treatment options in terms of patient-centred improvement, motion preservation and adjacent segment degeneration. SEARCH METHODS: A comprehensive search in Cochrane Back Review Group (CBRG) trials register, CENTRAL, MEDLINE, EMBASE, BIOSIS, ISI, and the FDA register was conducted. We also checked the reference lists and performed citation tracking of included studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing total disc replacement with any other intervention for degenerative disc disease. DATA COLLECTION AND ANALYSIS: We assessed risk of bias per study using the criteria of the CBRG. Quality of evidence was graded according to the GRADE approach. Two review authors independently selected studies and assessed risk of bias of the studies. Results and upper bounds of confidence intervals were compared against predefined clinically relevant differences. MAIN RESULTS: We included 40 publications, describing seven unique RCT's. The follow-up of the studies was 24 months, with only one extended to five years. Five studies had a low risk of bias, although there is a risk of bias in the included studies due to sponsoring and absence of any kind of blinding. One study compared disc replacement against rehabilitation and found a statistically significant advantage in favour of surgery, which, however, did not reach the predefined threshold for clinical relevance. Six studies compared disc replacement against fusion and found that the mean improvement in VAS back pain was 5.2 mm (of 100 mm) higher (two studies, 676 patients; 95% confidence interval (CI) 0.18 to 10.26) with a low quality of evidence while from the same studies leg pain showed no difference. The improvement of Oswestry score at 24 months in the disc replacement group was 4.27 points more than in the fusion group (five studies; 1207 patients; 95% CI 1.85 to 6.68) with a low quality of evidence. Both upper bounds of the confidence intervals for VAS back pain and Oswestry score were below the predefined clinically relevant difference. Choice of control group (circumferential or anterior fusion) did not appear to result in different outcomes. AUTHORS' CONCLUSIONS: Although statistically significant, the differences between disc replacement and conventional fusion surgery for degenerative disc disease were not beyond the generally accepted clinical important differences with respect to short-term pain relief, disability and Quality of Life. Moreover, these analyses only represent a highly selected population. The primary goal of prevention of adjacent level disease and facet joint degeneration by using total disc replacement, as noted by the manufacturers and distributors, was not properly assessed and not a research question at all. Unfortunately, evidence from observational studies could not be used because of the high risk of bias, while these could have improved external validity assessment of complications in less selected patient groups. Non-randomised studies should however be very clear about patient selection and should incorporate independent, blinded outcome assessment, which was not the case in the excluded studies. Therefore, because we believe that harm and complications may occur after years, we believe that the spine surgery community should be prudent about adopting this technology on a large scale, despite the fact that total disc replacement seems to be effective in treating low-back pain in selected patients, and in the short term is at least equivalent to fusion surgery.

Autografts for spinal fusion: osteogenic potential of laminectomy bone chips and bone shavings collected via high speed drill.

In case of revision or minimal invasive spinal surgery, the amount of autograft possibly harvested from the lamina and the spinous processes is limited. Ekanayake and Shad (Acta Neurochir 152:651-653, 2010) suggest the application of bone shavings harvested via high speed burr additionally or instead, but so far no data regarding their osteogenic potential exist. Aim of the study was to compare the osteogenic potential of bone chips and high speed burr shavings, and to evaluate the applicability of bone shavings as an autograft for spinal fusion. Bone chips and shavings from 14 patients undergoing spinal decompression surgery were analyzed using in vitro tissue culture methods. Osteoblast emigration and proliferation, viability and mineralization were investigated and histological evaluation was performed. Bone chips from all patients showed successful osteoblast emigration after average 5.5 days. In contrast, only 57% of the corresponding bone shavings successfully demonstrated osteoblast emigration within an average time span of 14.8 days. Average osteoblast mobilisation was 1.25 × 10(6) cells per gram from bone chips and 1.73 × 10(5) cells per gram from the corresponding bone shavings. No difference was observed regarding cell viability, but population doubling times of bone chip cultures were significantly lower (50.5 vs. 121 h) and mineralization was observed in osteoblasts derived from bone chips only. Although some authors suggest the general applicability of laminectomy bone shavings as autografts for spinal fusion, autologous bone grafts obtained from laminectomy bone chips are superior in terms of cell delivery, cell proliferation and mineralization.

[Keel-based lumbar total disk replacement: Prodisc-L and Prodisc-O]. / Kielbasierte lumbale Bandscheibenprothesen: Prodisc-L und Prodisc-O.

OBJECTIVE: Improvement of chronic low back pain caused by degenerative disc disease. Maintenance of motion in the treated segment. Reduction of possible adjacent-segment degeneration. INDICATIONS: Chronic low back pain, resistant to conservative therapy due to painful degeneration of the intervertebral disks ("degenerative disk disease"). CONTRAINDICATIONS: Spondylolisthesis, scoliosis, osteoporosis, infection, spinal stenosis, degeneration of the vertebral articulations, (pathologic) fractures. SURGICAL TECHNIQUE: The intervertebral disk is removed via an anterior (Prodisc- L) or anterolateral (Prodisc-O) approach. The segment is sufficiently mobilized, if necessary, by release of the posterior longitudinal ligament. After end-plate preparation, a groove for the keel is chiseled, the end plates are inserted, and the inlay is securely locked in place. POSTOPERATIVE MANAGEMENT: Careful beginning of food intake for prophylaxis of ileus. Early mobilization starting on the 1st day after surgery. RESULTS: From April 2002 to February 2008, 87 Prodisc-L intervertebral disk prostheses were implanted in 71 patients (43 women, 28 men, average age 45 years). Clinical evaluation was based on the visual analog scale (VAS), the Oswestry Disability Index (ODI), and the SF-36 questionnaire. Follow-up assessment also included radiographic views of the lumbar spine in two planes in flexion and extension and standing. The follow-up interval for all patients was at least 1 year and 2 years for 62 patients. After 2 years, 42 patients were very satisfied with the operation, 13 patients were satisfied, and seven patients were less satisfied. The clinical parameters recorded on the VAS, ODI, and SF-36 improved from 7.5 to 3.5 (VAS), 46.0 to 22.9 (ODI), and 30.5 to 44.8 (SF-36, Physical Component Summary Score) from the time of preoperative assessment to the 2-year follow-up.

Life quality after instrumented lumbar fusion in the elderly.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To review the clinical outcome on elderly patients after spinal instrumented fusion. SUMMARY OF BACKGROUND DATA: Although lumbar fusion in elderly patients has increased rapidly, there are only few and conflicting results regarding the clinical outcome. METHODS: This retrospective review evaluated 195 patients aged 70 to 89 who underwent lumbar spinal fusion. All 195 patients had follow-ups after 6 weeks, 1 year, and 2 years, including clinical evaluation as well as visual analog scale score, Oswestry Disability Index, and Short Form health survey. RESULTS: Elderly patients benefit from spinal fusion. Back and leg pains were initially reduced by >50%, with a slight deterioration over a 2-year period. Pain medication was reduced in 69% of the patients, and 89.7% of the patients were satisfied. CONCLUSION: Age itself cannot be considered a contraindication.

[Implantation of the ProDisc intervertebral disk prosthesis for the lumbar spine]. / Die Implantation der lumbalen Bandscheibenprothese vom Typ ProDisc.

OBJECTIVE: To eradicate treatment-resistant lower back pain caused by painful degeneration of the intervertebral disks. To avoid the disadvantages of alternative fusion surgery, especially degenerative wear and tear on adjacent segments, by maintaining the mobility of the affected motion segments. INDICATIONS: Treatment-resistant lower back pain due to painful degeneration of the intervertebral disks ("degenerative disk disease"). CONTRAINDICATIONS: Spondylolisthesis, scoliosis, osteoporosis, infection, spinal stenosis, degeneration of the vertebral articulations. SURGICAL TECHNIQUE: The intervertebral disk is excised through an anterior approach. It is essential to retain good mobility of the motion segment, if necessary, by resection of the posterior longitudinal ligament. After revitalization of the vertebral base and cover plates and chiseling of a groove for the keel of the prosthesis, the upper and lower prosthetic plates are inserted and the polyethylene inlay is locked into place. RESULTS: From April 2002 to May 2004, 36 ProDisc (Synthes Spine, West Chester, PA, USA) modular intervertebral disk prostheses were implanted in 34 patients (26 women, eight men, average age 44.3 years). Clinical evaluation was based on the visual analog scale (VAS), the Oswestry Disability Index (ODI), and the SF-36 Questionnaire. Follow-up assessment also included radiographic views of the lumbar spine in two planes in flexion and extension and standing. The follow-up interval for all patients was at least 1 year and 2 years for 14 patients. 26 patients were very satisfied with the operation, five patients were satisfied, and three patients were less satisfied. The clinical parameters recorded on the VAS, ODI and SF-36 improved from 7.4 to 2.8 (VAS), 48.0 to 13.1 (ODI) and 31.3 to 44.2 (SF-36, Physical Component Summary Score) from the time of the preoperative assessment to the 1-year follow-up. The range of motion at the segment with the implanted prosthesis was 10 degrees on average at L4/5 and 7 degrees on average at L5/S1 1 year postoperatively.

Is there an indication for prophylactic balloon kyphoplasty? A pilot study.

Vertebroplasty and kyphoplasty are associated with a recurrent fracture rate of 2.4% to 23%, which is lower than the general natural history of untreated osteoporotic fractures. Some authors suggest the risk of refracture at adjacent vertebra will be reduced by prophylactic stabilization. We therefore compared the refracture rate after prophylactic balloon kyphoplasty in 60 patients randomized into groups with either monosegmental balloon kyphoplasty or adjacent prophylactic balloon kyphoplasty. The level (superior versus inferior) for prophylactic stabilization was chosen according to fracture type. We evaluated patients for 12 months using radiographs, visual analog scale scores, and SF-36 scores. We followed 23 of 30 patients in the monosegmental group and 27 of 30 patients in the prophylactic group. We observed no difference in the 1-year refracture rates between the two groups (five patients in the monosegmental group and seven in the prophylactic group). Leakage into the disc was the presumed cause of adjacent fractures in 50% of the patients. Disc leakage and refracture rate did not correlate as a result of the low patient number. Based on our data, we believe there is no indication for prophylactic stabilization of adjacent segments with balloon kyphoplasty.